SOLUTION: if sec(u)= -25/7 and pi<(u)<3pi/2 , compute cot(u) ?

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Question 955270: if sec(u)= -25/7 and pi<(u)<3pi/2 , compute cot(u) ?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
cos%28u%29=-7%2F25
cos%5E2%28u%29%2Bsin%5E2%28u%29=1
49%2F625%2Bsin%5E2%28u%29=625%2F625
sin%5E2%28u%29=%28625-49%29%2F625
sin%28u%29=-24%2F25
I choose the negative value of the square root since the angle is confined to the 3rd quadrant where sin is negative.
So then,
cot%28u%29=cos%28u%29%2Fsin%28u%29
cot%28u%29=%28-7%2F25%29%2F%28-24%2F25%29
cot%28u%29=7%2F24